title: Male-female differences in left-handedness in Sardinia, Italy.
abstract: Males were consistently found to be more likely than females to report left-hand preference in single-hand tasks, but the literature reports negative results too. Using data from a large sample in Sardinia, we aimed at testing the links of left-handedness with sex, age, residence, and seasonality of birth. A total of 4239 participants (males = 1589; females = 2650) were recruited in public places such as high schools, university classes, or gyms in one of the major islands of Italy. Hand preference was established with the question: Which hand do you normally use to write legibly? The monthly distribution of births was studied with the Rayleigh test. In the sample, 270 female participants reported left-hand preference in writing (10.2%) versus 161 male participants (10.1%). Left-hand preference in writing was negatively related to age, with increasing left-hand preference in the younger generations. Left-hand preference in writing was not more common in urban than in suburban or rural settings. The month of birth was found to have a seasonal effect on the left-handed (p=.031) but not on the right-handed (p=.80) participants, and this seasonal effect was more evident in males (p=.04) than in females (p =.26). In our sample males were not more likely to report left-hand preference in writing than females. On the other hand, left-hand preference does vary by age and, in all likelihood, this is an effect of the reduced cultural pressure to write with the right hand in the younger generations.
authors.affiliation: Department of Psychology, University of Cagliari, Cagliari, Italy. apreti@tin.it
authors.forename: Antonio
authors.initials: A
authors.lastname: Preti
authors.forename: Davide
authors.initials: D
authors.lastname: Sisti
authors.forename: Marco B
authors.initials: MB
authors.lastname: Rocchi
authors.forename: Monica
authors.initials: M
authors.lastname: Busca
authors.forename: Marcello
authors.initials: M
authors.lastname: Vellante
authors.forename: Maria Valeria
authors.initials: MV
authors.lastname: Camboni
authors.forename: Donatella Rita
authors.initials: DR
authors.lastname: Petretto
authors.forename: Carmelo
authors.initials: C
authors.lastname: Masala
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004292:Dominance, Cerebral / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006236:Handwriting; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology; D012727:Sex Characteristics; D011795:Surveys and Questionnaires; D055815:Young Adult